firewire: fw-ohci: fix IOMMU resource exhaustion
There is a DMA map/ unmap imbalance whenever a block write request
packet is sent and then dequeued with ohci_cancel_packet. The latter
may happen frequently if the AR resp tasklet is executed before the AT
req tasklet for the same transaction.
Add the missing dma_unmap_single. This fixes
https://bugzilla.redhat.com/show_bug.cgi?id=475156
Reported-by: Emmanuel Kowalski
Tested-by: Emmanuel Kowalski
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c
index 46610b0..ab9c01e 100644
--- a/drivers/firewire/fw-ohci.c
+++ b/drivers/firewire/fw-ohci.c
@@ -974,6 +974,7 @@
packet->ack = RCODE_SEND_ERROR;
return -1;
}
+ packet->payload_bus = payload_bus;
d[2].req_count = cpu_to_le16(packet->payload_length);
d[2].data_address = cpu_to_le32(payload_bus);
@@ -1025,7 +1026,6 @@
struct driver_data *driver_data;
struct fw_packet *packet;
struct fw_ohci *ohci = context->ohci;
- dma_addr_t payload_bus;
int evt;
if (last->transfer_status == 0)
@@ -1038,9 +1038,8 @@
/* This packet was cancelled, just continue. */
return 1;
- payload_bus = le32_to_cpu(last->data_address);
- if (payload_bus != 0)
- dma_unmap_single(ohci->card.device, payload_bus,
+ if (packet->payload_bus)
+ dma_unmap_single(ohci->card.device, packet->payload_bus,
packet->payload_length, DMA_TO_DEVICE);
evt = le16_to_cpu(last->transfer_status) & 0x1f;
@@ -1697,6 +1696,10 @@
if (packet->ack != 0)
goto out;
+ if (packet->payload_bus)
+ dma_unmap_single(ohci->card.device, packet->payload_bus,
+ packet->payload_length, DMA_TO_DEVICE);
+
log_ar_at_event('T', packet->speed, packet->header, 0x20);
driver_data->packet = NULL;
packet->ack = RCODE_CANCELLED;